Clinical Results and Pharmacokinetics of Sorafenib in Chronic Hemodialysis Patients with Metastatic Renal Cell Carcinoma in a Single Center

Objective: We investigated the safety and feasibility of sorafenib in patients with end-stage renal disease undergoing hemodialysis by examining the influence of pharmacokinetic parameters to their benefit and also the occurrence of drug-related adverse events of sorafenib. Methods: Ten patients with metastatic renal cell carcinoma undergoing hemodialysis received sorafenib. Initial dose was 200 mg once daily, and the dose was increased up to the maintenance dose of 200 mg twice daily. The pharmacokinetic study was performed after a steady state was reached with 200 mg twice daily in six patients. Results: Complete response occurred in one patient, partial response in three, stable disease in four and progressive disease in two. Median progression-free survival was 6.3 months. Serious adverse events were found in nine patients, including a Grade 5 subarachnoid hemorrhage and a Grade 4 cerebellar hemorrhage. In the pharmacokinetic study, the geometric mean of maximum concentration and area under the curve from 0 to 10 h of plasma concentration were similar on the day of hemodialysis and the day off hemodialysis. These data were lower than those from Japanese people with healthy kidneys and normal kidney function. There was no association between objective response or the occurrence of serious adverse events and pharmacokinetic parameters. Conclusions: Treatment with sorafenib of patients with metastatic renal cell carcinoma undergoing hemodialysis appears to be feasible, but we express some concern about the higher incidence of serious adverse events even with the reduced dose. However, clinical efficacy was not compromised.